Sausages filled with pasty material are produced by means of filling machines in which the pasty material is at first filled into a funnel, conveyed via a conveyor system into a filling tube and discharged by the filling tube into a sausage sleeve. During the filling process, the filling material is under pressure and compressed. When the filling process is ended, e.g. when a new sausage sleeve is put onto the filling tube, the filling material that remains in the filling material intake (between the conveyor system and the end of the filling tube) is relieved due to the air content in the filling material, which amounts to approximately 0.5 to 10%. As the filling material cannot expand towards the conveyor system, this filling material expansion leads to escaping of a part of the filling material on the open filling tube end. This effect is undesired as, on one hand, the escaped filling material can moisten and therefore damage sensitive sausage sleeves and as there might be split skins during production on the other hand. Further, escaping filling material leads to weight inaccuracies of the first portion(s) of a subsequent skin roller. The escaped filling material cannot be fed into the filling process anymore and is consequently lost. Another disadvantage consists in that this filling material soils the machine during production. However, filling material can also escape due to viscosity. For example, the filling material may escape due to a low viscosity of the filling material.
Based on this, the underlying purpose of the present disclosure is to provide a method and a device to prevent or at least to minimize the escape of filling material at the end of the filling tube when finishing the filling process.
In the method according to the present disclosure for filling of sausage sleeves with pasty material through a filling tube, the pasty material is fed into the filling tube through an opening on its rear end in the axial direction. At the end of the filling process, the filling tube is driven out of its filling position back to an axially arranged closing element in the axial direction, whereby the opening is closed. Hence, the flow of pasty material can be locked towards the filling tube. Hence, the expanding air in the filling material cannot push the filling material through the filling tube towards the outside anymore. Only the filling material that is located in the filling tube can still expand towards the end of the filling tube. According to the present disclosure, the pasty material can arrive in the filling tube without deflection or without any major cross-section constriction during the filling process. The pasty material thereby flows simply in the feeding device around the closing element into the filling tube. In case of the solution, the pressure of the pasty material does not have to open the throughput cross-section against an outside energy (e.g. spring) as it would be the case for example if a check valve were used. If, at the end of the filling process, the filling tube is pushed axially to the rear, i.e. against the transport direction of the pasty material, the filling tube can for example be pulled out of a skin brake to put on a new sausage sleeve without a swiveling process and hence a complex mechanism being required. The filling tube can be closed in a fast and simple way after the filling process. Then, the filling tube can be moved again from an end position to the filling position to the front. For example, the filling tube may be moved axially in a direction opposite of the end position in order to be moved to a front position.
According to one embodiment, the filling tube and the closing element will be displaced together over a second path S2 in the axial direction to the rear into an end position after having moved the filling tube over a first path S1 onto the closing element and therefore having closed the opening. This means that, if the filling tube is for example moved to the rear in the axial direction for putting on a new sausage sleeve, the opening will already be closed towards the rear during a part of the way so that no pasty material can enter the filling tube anymore. Therefore, the filling tube opening and hence the flow of the pasty material into the filling tube will already be locked after a short movement path. It will be particularly advantageous if the second path S2≥the first path S1.
It will be advantageous if the filling tube and the closing device are connected to one another via a holding device in a way that the opening also remains closed during the joint movement of the filling tube and the closing element. Particularly easy to implement is a respective connection via a magnetic holding device, wherein the closing element sticks to the filling tube due to magnetic force. However, other detachable holding devices such as snap devices are also possible.
Advantageously, it is provided that the filling tube will again be moved away from the closing element into a filling position, for example after having been closed and after a new sausage sleeve has been put on. The closing element and the filling tube may be moved jointly out of the end position in the opposite axial direction back to the front. In this process the closing element and the filling tube are still connected to one another through the holding device. Before the filling tube is arranged in the filling position again, the opening of the filling tube is opened again while the closing element and the filling tube are moving apart. In one example, the opening is opened after a path that is equivalent to the second path S2.
After being moved over the second path S2 in an axial direction towards the front, the closing element may be stopped once again. In at least one embodiment, the closing element reaches the end stop in this process. As the filling tube is moved further towards the front, the connection, e.g. magnetic connection, between the filling tube and the closing element is detached so that the opening is uncovered. The filling tube is subsequently put back into its filling position. If the closing element is for example kept in the end stop position by means of the further holding device, in particular by magnetic force, it can be avoided that the closing element is pulled and/or sucked back towards the conveyor system in a backsiphoning process of a conveyor system.
At the end of the filling process means for example that the filling tube moves back out of the filling position in the axial direction A when a conveyor system for feeding of the filling tube with pasty material is switched off. After the switch-off, the conveyor system can move in a backward direction to suck off potential remainders in a feeding device that is adjacent to the conveyor system and to compensate the reduction of the filling material volume as a consequence of the axial movement. The closing element, that has for example an elongated shape, e.g. has an elongated plunger, may be led in a guiding system during its axial movement. The closing element can be moved and/or driven through the filling tube and/or moved via a separate drive and/or for example by means of spring energy. If the closing element is moved through the filling tube, a respective device can be set up in a particularly simple and cost-efficient way.
In some applications, the filling tube can comprise for example a filling material feed tube as well as an axially arranged, detachable filling tube front section, wherein the front filling tube section is detached in the end position and wherein the front opening of the filling material feeding tube may be closed.
Therefore, for example the filling tube front section can be replaced, for example by turning the front filling tube section away via a turning system and by replacing it by a new filling tube section.
A device according to the present disclosure for filling of sausage sleeves with pasty material is provided. The device comprises a filling tube that is arranged in an axially movable way and a feeding device through which the pasty material can be fed in axially from a conveyor system on an opening at the rear end of the filling tube. According to the present disclosure, an axially arranged closing element may be provided by means of which the opening at the end of the filling tube can be closed if the filling tube is moved onto the closing element. In this process, the device can have a drive that can move the filling tube axially back and forth.
Thereby, the closing element may be arranged in an axially movable way in the feeding device, in particular as an axially movable plunger whose front end closes the filling tube opening.
The filling tube and the closing element can be moved jointly in the axial direction to the rear into an end position. The filling tube can be connected to the closing element by means of a holding device, in particular of a magnetic holding device that can be provided easily and cost-efficiently. In at least one example, the axial movement of the closing element to the front is limited by a first stop device, in particular an end stop, wherein the closing element is held in the end stop position, for example, by a further holding device, in particular by a magnetic holding device. This end stop enables the filling tube to move further to the front whereas the closing element is stopped so that the filling tube and the closing element can move apart and that the opening at the rear end of the filling tube can be opened once again. The holding device ensures that the closing element will not be pulled to the rear during a backsiphoning process of the pump.
The filling pipe and/or the closing element are held in the end position by a second stop device, in particular a second end stop. If the closing element runs onto the first or second end stop, the filling tube can be positioned correctly in its filling position and end position by means of the closing element in a simple way.